Lading bar mechanism for railway car doors



Jan. 9, 1968 J. A. DUFFIE 3,362,354

LADING BAR MECHANISM FOR RAILWAY CAR DOORS Filed Feb. 23, 1965 's' Sheets-Sheet 1 FIG. I

Y INVENTOR. 36 JAMES APDUFFIE ATTORNEYS Jan. 9 1968 3,362,354

mums BAR MECHANISM FOR RAILWAY CAR DOORS J. A. DUFFIE s Sheets-Sheei 2 I INVENTOR- JAMES A DUFFIE 4 448 441 Filed Feb. 23, 1965 ATTORNEYS Jan 9, 1968 J- A. DUFFIE LADING BAR MECHANISM FOR RALLWAY CAR DOQRS 3 Sheets-Sheet 5 Filed Feb 23, 1965 INVENTOR. JAMES A. DUFFIE BY 4m; 61 444 ATTORNEYS United States Patent 3,362,354 LADING BAR MECHANISM FOR RAILWAY CAR DOORS James A. Dulfie, Youngstown, Ohio, assiguor to The Yfilllingstown Steel Door Company, a corporation of 0 '0 Filed Feb. 23, 1965, Ser. No. 434,231 7 Claims. (Cl. 105-369) This invention relates broadly to railway box car doors and more particularly to a retractable lading bar mechanism to be used therewith.

The types of movable doors customarily used with railway cars can generally be classified as plug doors and slidable doors. The plug door provides a flush, planar inner surface, colinear with the inner surface of the railway car, so that a good weather seal is available for the railway car upon which it is employed. However, generally complicated mechanisms including cranks, levers, and other supporting and moving means must be provided with plug doors in order to alford both lateral movement of the door into and out of the door opening and longitudinal movement away from or toward the door opening. Sliding doors on the other hand, are operable to assume only diife-rential longitudinal positions relative to the door opening, along a track mounted to the outer side surface of the car.

In order to provide clearance for sliding doors, a space between the inner wall surface of the car and the inner surface of the door is required and a continuous coplanar surface between the inner surface of the door and that of the car wall is not available with railway cars utilizing slidable doors.

In the past, plug doors have been utilized when a good weather seal was necessary for the car with which it is to be used. For example, in refrigerator cars, or other types of weatherized cars, the plug door has been an absolute necessity in order to provide a proper sealing relationship and avoid leakage of refrigerated air and ultimate spoilage from occur-ring. On the other hand, where the material being shipped is non-perishable, for example, lumber, boxes, or non-perishable lading in general, the sliding doors have been more widely used. It is, of course, obvious that the sliding door is of more economical design, and that where appropriate, is used in preference to the expensive plug type door. However, it has been found that the space between the inner wall surface of the car and the inner surface of the. door, the door well, is undesirable and permits cargo shifting.

It should be appreciated that a railway car is loaded by placing freight boXes, cargo, etc., from the forward and terminals ends of the car progressively toward a side door. Ultimately the final unit-s of cargo to be placed are positioned contiguous with the inner side wall of the car. Obviously, with sliding car doors a door well remains, and it is into this door well that the cargo may tumble or shift. Damage to the door and, as well, to the cargo are often the direct result of this disorder. In addition, further problems and frustrations are encountered in attempting to open a door upon which the cargo has shifted. Therefore, to overcome the possibilities of lateral cargo movement a lading restraining arrangement is desirable. It is, accordingly, the prime object of this invention to permit usage of conventional sliding doors with railroad cars, and, at the same time, do away with the door well which exists between the inner surface of the car wall and the inner surface of the sliding door.

A further object of this invention is to provide a lading bar retracting mechanism, to be used with conventional sliding doors, which is operable between retracted and extended positions from without the railway car.

It is still another object of this invention to provide a retractable lading bar arrangement to be used with conventional railway car sliding doors to prevent lateral shifting of internal loads into the doorway of the car.

It is still another object of this invention to provide a lading bar arrangement for conventional railway sliding doors which is actuatable into an operable extended position to provide a continuous coplanar relationship with the inner surface of the railway car door, and which cooperates with the door post of the car to provide for internal load distribution over the entire railway car wall thereby to remove damaging localized forces acting on the door.

It is still another object of this invention to provide a retractable lading bar mechanism for use in conjunction with conventional railway car sliding doors, which is operable to remain, without slippage, during use either fully opened or fully closed, upon being placed in either of the said positions.

It is yet another object of this invention to provide a lading bar retracting mechanism for use with sliding railway car doors which is operable to assume a fully extended position after the sliding door with which it is associated has assumed a closed position in order to prevent load or cargo shifting into the doorway well, and is also operable to assume a fully retracted position to permit longitudinal movement of the sliding door relative to the doorway.

These and other objects of the invention are fully achieved by my novel retractable lading bar mechanism in a manner which will be further disclosed hereinafter, but for the present is first briefly described as including a railway car having a slidable door which is operable to assume differential positions relative to a side door opening in the car, between a fully opened position and a fully closed position, by movement of the door across the door opening, along a longitudinal track mounted proximate thereto. A horizontally movable lading bar mechanism, including a lading surface, is operably mounted along the inner surface of the slidable door, in a manner which provides for adequate clearance of the sliding door relative to the outer surface of the railway car, is also provided. A manually operable lading bar operating mechanism is mounted along the outer surface of the door to permit actuation of the mechanism, upon the door assuming a fully closed position, for extending the lading surface inwardly of the door to assume a vertical position, coplanar with the inner surface of the railroad car and thus provide a continuous coplanar surface therewith to, accordingly, prevent cargo or load shifting into the doorway well.

To the accomplishment of the foregoing and related ends, said invention consists of the means hereinafter fully described and particularly pointed out in the claims, the following description setting forth in detail one approved means of carrying out the invention, such disclosed means, however, constituting but one of the various ways in which the principles of the invention may be used and carried out.

Other objects, togetherwith the foregoing, are obtained in the embodiments of the invention described in the accompanying description and illustrated in the accompanying drawings, wherein like reference numerals indicate like parts, in which:

FIGS. 1 is a side elevation, partially broken away, of a railway car having a sliding door equipped with a lading bar mechanism of the instant invention;

FIG. 2 is a sectional view taken along the line 2-2 of FIG. 1 and indicates the extended position of the lading plate and associated lading bars, as well as the exterior means for operation thereof, and the shock distribution cooperation of the lading plate with a door post;

FIG. 3 is a side elevational view of FIG. 2 with the lading bar mechanism and lading plate in its retracted position;

FIG; 4 is a sectional elevational view taken along line 44 of FIG. 1 showing the door construction and the sliding cooperation of the door along associated car mounted tracks; and

FIG. 5 is a sectional side elevational view taken along the line 55 of FIG. 1 showing the relationship of the lading bar mechanism and plate in a retracted position, relative to the door.

Referring to the embodiment of the invention illustrated in FIGS. 1 through 5, inclusively, the numeral designates a portion of the side wall of a railway box car which is provided with a conventional door opening 11. The horizontal extent of this door opening is defined by a means of front and rear channel shaped door posts 12 and 13. Post 13 being provided with a longitudinal indenture 26 which cooperates with one edge of the lading plate, in the fully extended position of the lading mechanism, to distribute any shock imparted thereto, over the door structure as well as to the lading bar and its associated mechanism. This will be treated in greater detail hereinbelow. The vertical extent of the door opening 11 is defined by means of a threshold plate 14 and a side plate 15 of any desired construction.

Secured to the front door post 12 and extending outwardly therefrom is a front door stop 16 which is adapted to cooperate with the door 17, an more particularly, with a flange bumper element 18 operable mounted forwardly thereof. Secured to the front door post 12 is a combined post protection angle and spark strip 22 which as herein after described is adapted to cooperate with the door 17 to provide a seal for the rear edge of the door.

The threshold plate 14 is supported in a conventional manner upon angle side sill 28 which may be re-enforced by channel shaped member 30, secured in any desired manner to the inwardly extending horizontal leg 32 of the side sill. A door supporting track 34 is carried by the side wall by means of a plurality of spaced track brackets 36 which are secured to and project outwardly from the car side wall.

The side plate 15 is customarily provided with a downwardly extending flange 40 to which a substantially J- shaped header 42 is secured and positioned in the manner illustrated in FIG. 4 of the drawings. A top door retaining member 44 is secured to the flange 40 of the side plate and projects outwardly therefrom in a form of a substantially channel-shaped member formed by the spaced flanges 45 and 46 and the vertical Webb 48. The top door retainer 44 is re-enforced by means of angularly disposed plates 49 which are welded to the door retainer.

The dorway opening 11 hereinabove described is adapted to be closed by means of a door 17 which is movable along the door supporting track 34 in a conventional manner. The door 17 is of light weight and may be formed of aluminum or any other suitable material. The corregated or ribbed design designated generally by the numeral 52, and other details of the door construction is the subject of a patent, which issued to W. A. Beuchamp, Patent No. 2,902,122, granted on Sept. 1, 1959, and is of common ownership herewith. Reference is made to the mentioned patent for further detail regarding the door construction. Cooperating with the door, and operably mounted thereto, is an outwardly extending substantially horizontal flange, not shown, which is disposed above the door supporting track. With the door in a non-moving position, the outwardly extending substantially horizontal flange is utilized to support the door frictionally upon the track and prevent movement thereof. Accordingly, in order to provide for longitudinal movement of the door relative to the door supporting track it is necessary to lift the door and remove the frictional bearing relationship between the horizontal flange as well as to permit engagement of roller 56 with the door supporting track. It is, of course, necessary to provide appropriate means to prevent disengagement of the lower portion of the door from the supporting track 34 when the door is in its rolling position.

The lifting and supporting mechanism designated generally by the numeral 58 is described in detail in the patent which issued to Madland, No. 2,475,507, granted on July 5, 1949, of common ownership herewith, to which reference is made and which is incorporated herein. Accordingly, further detail description of the mechanism is not believed to be necessary except to state that the parts of the lift mechanism are preferrably formed of aluminum or light weight material.

A locking mechanism shown generally by the numeral 64 and which is made up of conventional elements, is provided at the front edge of the sliding door. Locking mechanism 60 secures the entire front edge of the door to the car side wall, and accordingly, prevents undesirable opening thereof when it is in its closed position.

Turning now to the drawings for further treatment of my lading restraining mechanism, it is seen that there is provided a vertically extending rotatably mounted rod 62. The rod 62 is mounted across the vertical extent of door 17 in appropriate bearing receptacles 64 for rotation thereabout. In addition, at approximate points, along the inner surface of the door 17 are fixedly mounted pivot pin hearing receptacles 6 9.

More particularly, the drawing illustrates two vertically spaced rows of pin bearing receptacles 69, with each row having a pair of horizontally aligned receptacles. It should, of course, be appreciated that obvious variations in design such as additional vertical rows, or additional number of receptacles 69 contained in the rows, may be incorporated without departing from the spirit of this disclosure. The pivot pin receptacles 69 are provided with appropriate bearings therein for rotatable receipt and mounting of pivot pins 76. Also provided is a lading plate or surface 72 which may be of solid or open grid design. The lading surface 72 is provided with a plurality of pivot pin insert bearings, for receipt of suitable pivot pins 70. The insert bearings are positioned to permit a proper bar link 79 connection with receptacles 69 and provide a pivotably association between said lading surfaces 72 and said door 17. Since the plurality of vertically spaced, horizontally movable linkages, which provide a pivotable association between the lading surface 72 and the inner surface of the door 17 are similar we shall only describe one set and reference is hereby made to FIGS. 2 through 5 for more detailed drawing description of this horizontal connection.

As shown in FIG. 2, the lading bar assembly under consideration is adapted, in its retracted position, the phantom portion of FIG. 2, to assume a flush contiguous relationship with the inner surface of door 17. With lading surface 72 in its retracted position the door well which normally exists between the inner surface of the car and the inner surface of door 17 is dramatically evident. However, upon the lading bar assembly assuming its extended position, projecting inwardly of the railway car in the area of the door well, we see that the lading surface 72 will assume an aligned, coplanar relationship with the inner surface of the railway car. Furthermore, we see that edge 82 of the lading surface 72 is extended to assume an almost contiguous relationship with the vertical indenture 26 provided in door post 13. In this manner any forces which are dealt to the lading bar will not be solely absorbed by the horizontally pivotable bar linkages, but will to some extent be absorbed by the door post 13 and thus add to the stability and rigidity of the system. With the lading bar assembly assuming an extended position we see that cargo which has been stacked flush with the inner surface of the car will be prevented from shifting into the door well by the extended lading bar surface 72.

As shown in FIGS. 2 and 3, which, of course, only illustrate one row of the horizontal extending parallelogram bar linkage mechanism, and which may be repeated at any number of desired vertical positions along the door, links 76 and 77 each have one end fixedly connected to rod '62 for rotative movement therewith. The other ends of links 76 and 77 are pivotably connected to the inset bearings 74 of lading bar 72 by means of pivot pin 70. Also, pivot pin bearing receptacles 69, which are fixedly mounted on the inner surface of door 17, are provided with suitable pins 70 for pivotly connecting one end of each of links 79 thereto. The other ends of link 79 are, in similar fashion to bar links 76 and 77, pivotly connected to the lading bar 72, by way of pivot pin 70' and lading bar 72 insert bearings 74. In this manner, upon a rotative force being provided to rotatably mounted rod 62, links 76 and 77 are moved in a horizontal plane between retracted and extended positions in accordance with the rotative movement of rod 6-2. Movement of links 76 and 77, upon rotation of rod 62, results in movement of the lading bar surface 72, since the opposite ends of links 76 and 77 are pivotably mounted therein; and, in turn, movement of surface 72 will impart a horizontal rotative force, in accordance with conventional parallelogram linkage operation, to links 79 about their pivot pins 70. In the fully extended position edge 82 of surface 72 assumes a horizontally latched position relative to the vertical channel 26 to further lock the plate in its extended position and help absorb and distribute any force dealt thereto by lading movement.

As has been stated, rod 62 is rotatably mounted to provide rotation in a first direction to extend, and in an opposite direction to retract, the lading bar 72. The means provided for imparting the rotative motion to rod 62 will now be discussed in greater detail. As shown in FIG. 1, an operating lever 84, which is manipulated from outside of the railway car, moves the lading bar 72 between either a retracted or extended stable position. For this reason the structure which includes lading bar 72 may be termed bistable means or means having two stable positions. Operating lever '84 is provided with a main vertical handle 85 and a bifurcated jaw portion 86. Bifurcated jaw portion 86 has an aperture extending transversely therethrough. J aw 86 is pivotly connected by means of a suitable pivot pin to an outwardly projecting rod 62 coupling member 87. Rod coupling member 87 being fixedly mountedto, and radially extending from, rod 62. Accordingly, it can be seen that handle 84 is capable of being pivoted about projecting rod coupling member 87 to assume differential vertical positions between the position shown in FIG. 1 and one whichis perpendicular thereto, by imparting a vertical arcuate manual force in an upwardly direction thereto. In addition, a handle retaining element 89 which has a -U-shaned cross-sectional desi n is also provided.

It can thus be seen, that with the operating lever in its vertical position as shown in FIG. 1, the locked position, that rotation of rotatably mounted rod 62 is prevented by the cooperation between handle 84 and handle retaining'elernent 89. With handle 84 in a locked position movement of the lading bar 72 is prevented and, accordingly, the bar 72 will remain locked in either of its two bistable positions. However, upon a desire to manipulate the lading bar from its current bistable position to its opposite bistable position, handle 84 is vertically elevated, from its position as shown to a horizontal position relative to projecting coupling 87. A rotative force is then applied to rod 62 by handle 84, and due to the fixed end conecteion of links 76 and 77 to rod 62, links 76 and 77 are moved in a horizontal plane between extended and retracted positions. Movement of links 76 and 77 in a horizontal plane, results in the lading bar 72 assuming differential vertical relationship between its extended coplanar position with the inner surface of the railway car and its contiguous retracted relation with the inner surface of door 17. Movement of lading bar 72 results in a horizontal planar movement in links 79, in a similar direction as links 76 and 77. It is, accordingly, accurate to describe the mechanism coupling the lading bar 72 to the inner surface of door 17 as a parallelogram link arrangement. However, it should be appreciated that any suitable equivalent mechanism, which is operative to permit a differential positioning of the lading bar relative to the inner surface of door 17, may be substituted.

Upon the lading bar being moved to its desired position handle 84 will be latched in its vertical position relative to handle retaining member 89 to thereby lock bar 72 in its desired position. In operation, after a railway car has been filled, with the last row of cargo being stacked contiguous with the inner side wall, sliding door 17 is moved to its closed position and the doors locked shut. It is, of course, clear that in a door 17 moving position lading bar 72 is locked in its retracted position,

relative to door 17, by handle 84 and retainer 89. Upon door 17 being moved to its closed position it is possible to move lading bar 72 into an opposite or extended, bistable condition and thus provide a lading supporting surface across the door well 11 and prevent cargo shifting. I provide, by way of my invention hereinabove described, a handle 84 which is workable from without the railway car to position a horizontally movable parallelogram bar mechanism into an extended position and thus vertically displace a pivotable associated lading bar 72 into a position coplanar with the inner wall surface of the railway car. Handle 84 and retaining member 89 then cooperate to lock lading bar 72 into its extended bistable position.

While lading bar 72 is in an extended position it is then impossible to open door 17. Accordingly, upon a desire to unload a railway car it is necessary to rotate handle 84, and thereby rotate mounting rod 62 to its opposite position relative to retainer member 89. Rotation of rod 62 results in repositioning the horizontally movable parallelogram bar mechanism to its stable retracted position contiguous to the inner surface of door 17. Movement of door 17 along its associated tracks 34 is .then permitted.

While it will be apparent that the embodiment of the invention hereindisclosed is well calculated to fulfill the objects of the invention, it will be appreciated that the invention is susceptible to modification, Variation and change without departing from the proper scope or fair meaning of the appended claims.

I claim:

1. In a railway car having a side wall formed with a door opening and provided with a sliding door mounted for movement along a door track proximate the door on the outer surface thereof, said sliding door being movable therealong between fully opened and fully closed positions, a door locking mechanism fixedly mounted upon the outer surface of the sliding door capable of locking said door to prevent further movement thereof upon assuming a fully closed position, a lading movement restricting arrangement to be used therewith comprising, a lading restricting surface, means having two stable positions fixedly mounted upon the inner surface of said door for proper side wall clearance and capable of movement between an extended stable condition and a retracted stable condition relative to said door, said lading surface being fixedly mounted to said means having two stable positions for movement therewith operating, means for operating said means having two stable positions, said operating means being fixedly positioned upon the outer surface of said sliding door, and being capable of assuming a lading surface extended or a lading surface retracted position, said lading surface assuming a retracted position contiguous the inner surface of the sliding door permitting unobstructed movement thereof along its associated track in accordance with said bistable operating means being in a lading surface retracted position, and assuming an extended position resulting in a coplanar surface with the inner side wall of said railway car upon said operating means being positioned to an extended position.

2. In a railway car having a side wall formed with a door opening and provided with a sliding door mounted for movement along a door track proximate the door on the outer surface thereof, said sliding door being movable between fully opened and fully closed positions, a door locking mechanism fixedly mounted upon the outer surface of the sliding door preventing further movement upon said door assuming a fully closed position, a lading restricting mechanism to be used therewith comprising, a lading surface, bistable means pivotably mounted upon the inner surface of said door for proper side wall clearance in its stable retracted state and capable of assuming an extended position into the door opening in a closed door position, said lading surface being pivotably mounted to said bistable means for movement therewith, means for operating said bistable means, said means being fixedly positioned upon the outer surface of said sliding door, and being capable of positioning said bistable means between a retracted stable state and an extended stable state, said lading surface being in a retracted position contiguous the inner surface of the sliding door permitting unobstructed movement thereof along its associated tracks in accordance with said operating means being in a retracted position, and assuming an extended position to result in a continuous coplanar surface being formed by the inner side wall of said railroad car in said lading surface upon said operating means being positioned to its extended position.

3. In a railway car having a side wall formed with a door opening and provided with a sliding door mounted upon a longitudinal door track proximate the door on the outer surface of the side wall, said door track permitting movement of the door therealong between fully opened and fully closed positions, a door opening filler device operatively mounted to the inner surface of said door, said filler device capable of assuming a fully extended operative position providing a coplanar continuous surface across the side wall door opening to prevent cargo displacement into the door opening comprising, bistable means operatively mounted upon the door for movement therewith, said bistable means having a stable retracted position and a stable extended position, and a lading surface operatively mounted upon said bistable means, said lading surface assuming a contiguous relationship with the inner surface of the sliding door upon said bistable means assuming a retracted stable position to accordingly permit unobstructed travel of the sliding door relative to the car side wall, said lading surface assuming an extended position providing a continuous inner wall surface across the side wall door opening upon said bistable means assuming its fully extended second stable state in a sliding door closed position.

4. In a railway car having a side wall formed with a door opening and provided with a sliding door mounted for movement along a track formed with the outer surface of the railway car, permitting movement of the door between fully opened and closed positions, a lading restricting mechanism to be used therewith comprising, a lading restraining surface, bistable means fixedly mounted upon the inner surface of said door for proper side wall clearance between said door and said side wall in a retracted stable state and capable of assuming an extended position into the door opening in a closed door position, means for operating said bistable means during door closed position to assume its second extended stable condition, said lading surface being in a retracted position contiguous said sliding door during cargo loading of said railroad car and movable upon said sliding door assuming a closed position, in accordance with said bistable means assuming its second stable extended state, to form a coplanar continuous inner wall surface and thereby prevent cargo shifting upon railroad car moving conditions.

door opening provided with a sliding door mounted for movement along the outer surface of the car between fully opened and fully closed positions, a lading movement restricting mechanism to be used therewith comprising, a planar lading sheet, means including a parallelogram link mechanism means pivotable connecting the inner surface of said sliding railway door and said planar lading sheet, said means pivotably connecting said planar lading sheet uponsaid sliding door between a fully retracted and a fully extended position, such that upon said lading sheet being in a retracted position contiguous the inner surface of the sliding door movement of said sliding door along the longitudinal door tracks is unobstructed, and upon said planar sheet being extended to its fully extended position said sheet assumes a continuous coplanar relationship with the inner surface of the railway car, and operating means mounted exteriorly of the door for operating said means including a parallelogram link mechanism between a retracted position against the door to their fully extended position inwardly of the railway car.

6. In a railway car having a side wall formed with a door opening provided with door posts defining the width of the door opening, the further provided with a sliding door mounted for movement along a longitudinal door track proximate the door on the outer surface thereof, said tracks permitting movement of the door therealong between fully closed and fully opened positions, a retractable lading bar mechanism for use with said sliding door, a lading surface, a rod rotatably mounted along the vertical surface of the car door, a plurality of bar links spacially connected for horizontal planar movement said plurality of bar links being distributed over a plurality of vertically spaced horizontally extending rows along the vertical extent of the door, each of said plurality of bar links having one end thereof pivotably connected with said lading surface, the other end of at least one of said bar links being vertically connected to said rotatably mounted vertical extending rod for rotative movement therewith, the remainder of said nonconnected ends of said plurality of links being pivotably connected to the inner surface of said door, and means mounted exteriorly of the door for rotating said rotatably mounted vertical rod, such that said lading surface assumes an inward retracted position contiguous the door to permit movement of the sliding door along the outer surface of said car, and a fully extended position proximate to and forward of a door opening defining post for load distribution thereover, said fully extending position resulting in a continguous coplanar relationship between the inner surface of the railway car and the lading surface to thereby prevent load shifting.

7. For use with a railway car having a slidable door which is operable to assume differential positions relative to a side door opening in the car, between a fully opened position and a fully closed position, by movement of said sliding door across the door opening, along a longitudinal track mounted proximate thereto, a lading plate surface, horizontally movable lading bar mechanism operably mounted along the inner surface of said slidable door to 5. In a railway car having a side wall formed with a pivotly connect said lading surface with the said inner surface of said slidable door, means for manually operating said lading bar mechanism, said manual operating means being mounted along the outer surface of the door, said manual operating means being positionable and locked in an extended and retracted position upon said door assuming a fully closed position, said manual operating means being actuatable to thereby extend the lading surface inwardly of the door to assume a vertical position coplanar with the inner surface of the railway car and thus provide a continuous coplanar surface therewith to thereby prevent cargo or load shifting into the door well, and being further operable to position said lading surface into a retracted position contiguous with the inner surface of the slidable door upon a desire to open said slidable door.

References Cited UNITED STATES PATENTS DAVID J. WILLIAMOWSKY, Primary Examiner.

0 DENNIS L. TAYLOR, HARRISON R. MOSELEY,

Examiners. AARON I. BREIER, Assistant Examiner. 

4. IN A RAILWAY CAR HAVING A SIDE WALL FORMED WITH A DOOR OPENING AND PROVIDED WITH A SLIDING DOOR MOUNTED FOR MOVEMENT ALONG A TRACK FORMED WITH THE OUTER SURFACE OF THE RAILWAY CAR, PERMITTING MOVEMENT OF THE DOOR BETWEEN FULLY OPENED AND CLOSED POSITIONS, A LADING RESTRICTING MECHANISM TO BE USED THEREWITH COMPRISING, A LADING RESTRAINING SURFACE, BISTABLE MEANS FIXEDLY MOUNTED UPON THE INNER SURFACE, BISTABLE MEANS FIXEDLY MOUNTED CLEARANCE BETWEEN SAID DOOR AND SAID SIDE WALL IN AA RETRACTED STABLE STATE AND CAPABLE OF ASSUMING AN EXTENDED POSITION INTO THE DOOR OPENING IN A CLOSED DOOR POSITION, MEANS FOR OPERATING SAID BISTABLE MEANS DURING DOOR 